During the operation of a loudspeaker, when the external drive current drives the voice coil to vibrate, an induced current in an opposite direction may also be incurred, especially when in high frequency, the self-inductance of the voice coil is so large that the induced current becomes large such that the operation of the loudspeaker is influenced to lead to damage to high frequency response.
In traditional a loudspeaker, a short-circuit ring is disposed below the spring washer and around the magnet to slow down the increasing speed of electrical resistance of the loudspeaker with the frequency. The short-circuit ring can counteract the effects on the magnetic field in the loudspeaker from the induced current of the voice coil, reduce the resistance of the loudspeaker in high frequency, play a role in decreasing harmonic distortion and the inductance of voice coil.
In extant structural design, the short-circuit ring is generally disposed on the inside of the voice coil and the sleeve-connected on the T iron or spring washer; or is disposed on the inside of the magnetic steel or the U iron while being positioned on the outside of the voice coil; or is used by means of combining the above two arrangements. However, in the above application of the short-circuit ring, the high calorific value of the cartridge of the T iron is not conducive to the magnetic stability during the operation of loudspeaker, and the effect of improving the harmonic distortion and non-linear distortion of the loudspeaker is still not very obvious.
Therefore, it is necessary to improve the design of extant loudspeaker magnetic circuit systems so as to decrease the harmonic distortion effectively and improve the overall acoustic performance of the loudspeaker. Furthermore, it is a technical problem to be solved by those skilled in the art to determine how to improve effectively the harmonic distortion and the non-linear distortion of the loudspeaker.